1.Field of the Invention
The invention relates to a photostructurable body having glass or glass-ceramic and processes for treating.
2. Description of Related Art
Optical components, which are based on the guidance and manipulation of light through structures, such as waveguides and gratings, are already known, for example in the sensor technology and telecommunications sectors. The primary medium for wave guidance is currently optical fibers; however, planar components are becoming more important on account of increased demands for miniaturization and increased complexity. The advantage of planar components is the possibility of producing a multifunctional component on just a single chip and thereby, for example, minimizing the coupling losses and also the production-related outlay for different components and therefore the costs of these components.
Although bifunctional or multifunctional components can also to a certain extent be produced in fibers, for example suitably doped fused silica (SiO2), in particular Ge-doped SiO2, is already being used for the production of Bragg gratings as (de)multiplexers, for example in wavelength filtering or for sensors in fibers. In this case, UV irradiation is used to produce an inhomogeneous defect distribution in the Ge-doped glass, and this, by changing the absorption coefficient, leads to changes in the refractive index. These gratings or other structures can also be produced in a similar way in certain Pb—, RE—(RE=Rare Earth) and Ag-doped glasses. Furthermore, suitable conditioning processes can be used for the targeted precipitation and subsequent selective etching of the microcrystals within the irradiated regions, as for example in the case of Corning 8603 Fotoform/FotoCeram or Hoya PEG-3.
It is also known that by irradiating different glasses with suitable high-energy pulses (fs pulses), it is possible to produce structures in glass. For example, positive changes in the refractive index in the range up to 10−2 have been produced by the fs writing of Ge-doped SiO2 glass or fused silica (K. Hirao et al., J. Non-Cryst. Solids 235, pp. 31-35, 1998).
Negative changes in refractive index have also been observed in borosilicates, sulfide glasses and lead glasses, cf. in this respect Corning WO 01/44871, PCT/US00/20651. By suitably setting the pulse energy and the writing speed, it is in this case possible to produce changes in refractive index without physically damaging the glass.